Delay action fuse



July 9, 1957 L. .T. MEISTER DELAY ACTION FUSE 2 Sheets-Sheet l Fild Feb. 27, 1945 LED T. Meilscer y 1957 T. MEISTER 2,798,432

DELAY ACTION FUSE Filed Feb. 27, 1945 2 Sheets-Sheet 2 I I E if f vh .H mm N v N -1 Len T- Me is cer N Q IR m czmwflm Gum/Map United States Patent This invention relates to an improved delay action fuse for rotatable projectiles and more particularly to projectiles of the armor piercing type.

The use of an armor piercing projectile containing a high explosive charge, having a shaped cavity for producing a concentrated, highly penetrating explosive jet, has been limited to projectiles of the nonrotative type due to the fact that the effect produced by the penetrating jet, resulting from a charge having a conical cavity, is greatly reduced when utilized with rotatable projectiles.

Consequently, the advantage gained through use of a rotatable projectile, namely, greater accuracy and increased penetrating power is at least partially offset by the decreased efiiciency resulting from the utilization of a charge that does not produce the penetrating jet.

. t is therefore a primary aim of the present invention ,to provide an improved construction of fuse wherein this deficiency can be overcome, and by the use of which a rotatable type projectile, with its accompanying .advantages, can be effectively employed in conjunction with an explosive charge having a conical cavity and-by means of which the conical cavity will function as efliciently as when used with a nonrotating projectile.

More particularly, .it is an object of the present inventlfOll to provide a fuse which will be partially armed by the rotation of the projectile in flight, which will thereafter be fully armed upon impact of the projectile with a target, and which will function to detonate the projectile charge after the rotation of the projectile has ceased or practically ceased, thereby allowing the armor piercing nose to penetrate the target before the high-explosive of the projectile is detonated; and so that the reduced efficiency of the penetrating jet with a rotating projectile will be eliminated due to the fact that the rotation of the projectile has ceased or practically ceased at the time that the jetis produced.

Other objects and advantages of the invention will hereinafter become more fully apparent in the. following description of the drawings which illustrate preferred embodiments thereof, and wherein:

Figure l is a fragmentary longitudinal, substantially central sectional view, of a projectile and taken substantially along a plane as indicated by the line 1-1 of Figure 2.

Figure 2 is an end view in elevation looking toward the rear end of the, fuse with the rear closure removed;

Figure 3 is a longitudinal sectional view of the fuse taken substantially along a plane as indicated by the line 3?3 of Figure l andshowi-ng' one of the firing pin carriers in its idle,'unar med position;

Figure 4 is a longitudinal sectional view of the fuse, taken along substantially the same plane as Figure l, and showing the firing pin carriers in partially armed positions;

Figure Sis a sectional viewof'lthe fuse, similar to Figure 4, s'howing'the firing pin carriers in fully armed positions;

Figure 6 is a sectional view of the fuse, similar to Figure "ice 4, showing the firing pin carriers in position to detonate the fuse;

Figure 7 is a longitudinal sectional view of a modified form of the invention taken along substantially the same plane as Figure -l; and 1 Figure 8 is a longitudinal sectional view of. the fuse, shown in Figure 7 and taken substantially along a plane asindicated-by the line -88 of Figure 7.

Referring more particularly to the drawings, 10 designates'generally arotatable type projectile such as an artillery shell and which includes a shell casing 11, an armor piercing nose 12, a shaped high-explosive charge 13, and a fuse 14 disposed in the rear-end of the casing 11 for detonating the charge 13.

The nose 12 is of conventional design being formed of hardened steel and being provided with a longitudinally disposed,.axially'arrangedcavityor recess 15, which extends from its inner end .to adjacent its outer-or forward end. The rear end of the nose 12 is reduced slightly and threaded to engage the internally threaded and recessed open forward end of theshellcasing 11, as seen at 16.

A thin walled steel cone 17 (shown greatly exaggerated as to thickness in Figure l) is disposed in the casing '11 and isprovided witha flanged open end whichis clamped between the nose 12 and an inwardly extending annular shoulder 18 of the'casing 11. The conical member-17 extends inwardly'or rearwardly of the casing 11 and'forms a liningfor the conical cavity 19 of the charge 13. The

rear endof thecasingll is open and internally threaded'at 20-toreceive the enlarged, externally threaded portion 21 of the housing 22 offuse 13.

Fuse 14 has arestricted andtapered inner end 23 which fits a cavity 24 in the rear'end of the charge 13, and said restricted portion 23 is provided with a forwardly opening cavity containing abooster charge 24. The booster cavity is closed bya thin wall plug 25, which may be secured therein by a threaded connection or a pressed tit, and which separates the booster 24 from the main charge 13. The fuse housing 22 is provided, adjacent itsrear end, with corresponding segmental shaped chambers 26 and 27, and the restricted portion 23 of the fuse housing is provided with arcuately shaped recesses 28 and 29 whichopenrearwardly into the chambers 26 and 27, respectively. The chambers 26 and 27 are definedvby a diametrically disposed wall '30 and may bean integral part of a housing 22., This wall terminates short .of the rear face of the housing so that a plug 32.may be screwed into place, as shown in Figure 1, to abut wall 30 and completely enclose the aforesaid chambers. The two sides or faces of the wall 30 are flared adjacent their inner edges to form the inclined or beveled surfaces 33 which are provided with openings containing percussion caps 34 and 35. The housing 22 is provided with a flash passage .36, into which the percussicn caps 34 and 35 open and which is separated from the booster charge 24 by an inflammable disk 37, which is adapted to be destroyed by the flash from either percussion cap 34 or 35, so that the booster charge 24 will be detonatedby the discharge of either of the percussion caps.

As seen in dotted linesin Figure 2, the fuse housing 22 is provided with a diametrical bore 38 having internally threaded ends opening outwardly thereof, to receive threaded closures or plugs 39, and which extends through flash passage 36. As best illustrated in Figure 3, a plunger 40 is slidably mountedin each end of the bore 38 and an expansion coil spring. 41 is disposed between each plunger 40 and its plug .39, for biasing the plungers 40 inwardly and to the positions of Figure 3, for closing the flash passage 36 between theprirners 34 and 35 and the booster 24. The inner ends of plungers 40 are semicircular in cross section. The plungers 40 are provided with annular grooves 42, intermediate their ends, to receive spring pressed detents 43, when the plungers 40 are retracted out of the passage 36, for latching the plungers in a retracted, inoperative position wherein booster charge 24 is subject to the initiation of primers 34 and 35.

A shaft or pin 44 is disposed in the fuse 14 and longitudinally thereof, and extends through chamber 26, recess 28 and substantially through a bore 45 in the restricted portion 23. The shaft 44 is provided with a head 46 at its rear end having a portion 47 of diameter less than head 46 and of substantially the same diameter as that of sleeve 49. A sleeve 49 is disposed in the bore 45 and is provided with an enlarged externally threaded forward end 50 which engages the threaded, enlarged forward end 51 of the bore 45, for adjustably positioning the sleeve 49 relatively thereto. An externally and internally threaded annular plug 52 is mounted, in the outer, forward end of the threaded portion 51 and bears against the outer, forward end of the threaded sleeve portion 50 for locking and retaining the sleeve 49 in adjusted position relatively to the bore 45, and also engages the threaded, forward end of shaft 44, for fixedly positioning it. The rear end of the sleeve 49 is spaced from the forward end of portion 47, and forms an annular groove 53 therewith. The portion 43 of pin 44 forming the bottom of groove 53 is provided with a rounded recess 54. A pin, corresponding to the pin 44 and provided with a portion 55, and a sleeve 56, corresponding to the portion 47 and sleeve 49, are mounted in the same manner relatively to the chamber 2 7 and the recess 29.

A firing pin carrier 57 is eccentrically mounted on portion 47 and a corresponding firing pin carrier 58 is similarly mounted on portion 55. The carriers 57 and 58 are journaled upon the portions 47 and 55, respec tively, and said carriers are provided with corresponding beveled surfaces 59, disposed at the same angle as the surfaces 33, and from which protrude firing pins 60. The pins 44 and 55 and their sleeves 49 and 66 carry corresponding helical springs 61 each of which is anchored at its forward end in the sleeve, with which it is associated, and anchored at its rear end in the corresponding firing pin carrier. Said springs are initially tensioned so as to yieldingly urge the firing pin carriers inwardly or toward the wall 30, that is, to the position shown in Figure 2. The springs 61 also function as expansion springs for urging the firing pin carriers rearwardly and against the heads 46. The firing pin carriers 57 and 58 are each provided with a spring pressed plunger or detent 67. having a rounded inner end, as best seen in dotted lines in Figure 2, which normally bears against the enlarged portion 47 of the pin 44 or 55, with which it is associated, but which, when the carriers slide forwardly on the respective portions 44 and 45 in response to impact, snap into grooves 53 to maintain the carriers in their forward or partially-armed positions illustrated in Figure 5.

From the foregoing it will be apparent that the fuse 14, when in its normal, idle position, will be unarmed due to the fact that the firing pins 60 are held to the rear of the percussion caps 34 and 35 by the tension of the springs 61 on the firing pin carriers 57 and 58. Also, the plungers 40 are disposed in position to close the flash passage 36 between percussion caps 34 and 35 on the one hand, and booster charge 24 on the other, to thereby effectively prevent detonation of the booster 24. When the projectile is fired from a rifled weapon barrel, not shown, and is caused to rotate thereby on its longitudinal axis, the firing pin carriers 57 and 58 will be swung outwardly on the enlarged pin portions 47, by centrifugal force, to assume the positions as shown in dotted lines in Figure 2 and as illustrated in Figure 4. The carriers 57 and 58 will remain in this position during the flight of the projectile 10 and until impact of the projectile nose 12 with a target. The carriers 57 and 58, at that time, by inertia, will slide forward on the pins 44 and 55, respectively, and against the action of the springs 61, until the plungers 62 register with grooves 53, as illustrated in Figure 5. When the carriers are thus disposed, as seen in Figure 5, the plungers 62 will be spring urged into the grooves 53 and will be correctly disposed so that their rounded ends will project into the rounded recesses 54, to prevent the carriers from sliding rearwardly on the pins under the urgency of the springs 61, after the force of inertia has been spent. As the armor piercing nose 121 bores its way into the target, not shown, the rotation of the projectile 1t) will rapidly diminish until the centrifugal force exerted on the firing pin carriers, to urge them outwardly, is less than the force of the springs 61, tending to urge the carriers inwardly. However, the inward movement of the carriers 57 and 58 will be resisted by the spring plungers or detents 62 engaging the recesses 54 until the rotation of the projectile has substantially ceased, at which. time the springs 61 will exert sufficient force to overcome the resistance offered by the engagement of the spring pressed detents 62 with the recesses 54, to cam the plungers or detents 62 out of the recesses 54, to thereby permit the springs 61 to swing the carriers 57 and 5S forcibly inward. At the time of the inward movement of the carriers 57 and 58 they will be disposed so that on their inward swinging movement the firing pin 60 of the carrier 57 will engage and detonate the primer 34 and the firing pin 60 of the carrier 58 will similarly engage and detonate the primer 35. By proper balancing of springs 61, through adjustment of the sleeves 49, the inward movement of the carriers 57 and 58 will occur simultaneously to cause simultaneous detonation of the primers 34 and 35. The centrifugal force produced by the rotation of the projectile 10 in flight will have caused the plungers 40 to move outwardly in the bore 38 until the grooves 42 are registering with the plungers 43, at which time the plungers will have been spring biased into the groove, to thereby latch the plungers 40 in retracted position to expose the flash passage 36. Consequently, the flash occurring from the primers 34 and 35 passes through the passage 36 to detonate the booster 24- and the charge 13. The detonation of the charge 13 produces an intense jet due to the cavity 19, which jet, not shown, in the form of a fine stream and with great penetrating force, passes forwardly through the longitudinal center of the nose cavity 15, through the forward end of the nose 12 and into the target. Likewise, the simultaneous detonation of the primers 34 and 35 due to their angular relationship, as seen in Figure 1, results in a similar jet, of much less intensity, which more efiectively detonates the booster 24. However, should one of the carriers fail to function for any reason, the normal functioning of the firing pin of the other carrier, resulting in the detonation of only one of the primers would be sufiicient to detonate the booster 24. The final position of the carriers 57 and 58 with their firing pin 60 in engagement with the primers 34 and 35, respectively, is illustrated in Figure 6, and when thus disposed, the beveled surfaces 59 are parallel to the complementary surfaces 33.

The flash passage 38 is closed by the two corresponding diametrically opposed plungers 40 so that in case one of the plungers 40 is retracted and latched in a retracted position, due to the projectile 10 being accidentally dropped, the other plunger 40 will assume a position to close the flash passage 36 until the projectile has been fired, to thereby render the projectile positively bore safe.

In Figures 7 and 8 another embodiment of the invention is disclosed comprising a fuse, designated generally 63, which is adapted for use in conjunction with a rotatable type projectile, the ogive portion only which is shown, and which is designated generally 64. The fuse 63 is modified, as compared to fuse 14, to the extent that it is adapted to be mounted in the nose portion of the projectile 64 for detonating a booster and main charge, both of which are disposed to the rear of the fuse 63. Projectile 64, as illustrated, includes a projectile casing the forward part 'efwhrh is s'hOWnat G S and which is rnternally'recessed to receive a charge of high explosive,

designated 66. The forward end of the casing 65 is open and provided with an elongated'irit'ernally threaded portion 67 into the outer end of which is threaded the restricted rear end 68 of a substantially solid armor piercing nose 69. The fuse 63 is provided with a housing 70 which is externally threaded to engage the intermediate portion of the threaded casing opening 67, for mounting the fuse 63 therein, directly behind the nose 69. A boost er 71 includes a housing having an enlarged, threaded forward end 72 which is threaded'into the rear end of the threaded opening'67 and which is disposed directly behind the fuse 63. The forward end of the charge 66 is recessed to accommodate the booster 71. It is to be understood thatin the projectile, shown in Figure 7, the cavity type charge is not employed and the penetration of the projectile is accomplished entirely by the boring action of the hardened, armor piercing nose '69.

The construction of the fuse 63 differs only from the fuse 14 in that the flash passage 73 thereof extends rearwardly instead of forwardly and the bore 74, corresponding to the bore 38, is located in the wall behind, instead of in front of, the percussion caps 34 and 35. The

bore 73, at its forward end, is provided with a parabolic recess 75 into which the primers 34 and 35 extend, and at its rear end, here 73 communicates with an opening 76 in the closure 77 of the booster 71, so that the open- 76 combines with the bore 73 to form the flash passage between the primers 34 and 35 and the booster 71. The plungers 40, and the parts associated therewith, contained in the bore 74, correspond with and are identical tothe parts contained in the bore 38 Likewise, the fuse '63 is provided with segmental chamber 26 and 27, arcuate recesses '28 and '29, pins 44 and 55, carriers '57 and 58, and

springs 61, and the parts associated therewith, corresponding to and bearing thesame reference characters as like parts in the fuse '14.

The operation of the fuse '63 substantially corresponds to the operation of the fuse 14, that is, the carriers 57 and 58 are initially swung outward against the tension of the springs 61 by centrifugal force, after the projectile 64 is fired; thereafter move forwardly by inertia upon impact of the projectile with its target and are latched in a forward position; and are ultimately swung inwardly by the force of the springs 61,-after rotation of the projectile 64 has substantially ceased; so that detonation of the charge 66 will not occur until the projectile has penetrated the target to the maximum extent. The rotation of the projectile 64 in flight will cause the plungers to be retracted and engaged and latched in retracted positions for exposing the flash passage 73. When the firing pins 60 move into engagement with and detonate the primers 34 and 35, the flash from these primers will be deflected or reflected back off of the parabolic surface 75 through passage 73 and opening 76 for detonating the booster 71, which will in turn detonate the main charge 66. Should one of the primers fail to function, either due to defect therein or a failure of one of the firing pin carriers to operate correctly, the firing of the other primer will be sufficient to donate the booster charge 71 and in all likelihood will result in the detonation of the other primer.

Various modifications and changes in the embodiments of the invention as disclosed are contemplated and will obviously be resorted to, without departing from the spirit and scope of the invention, as hereinafter defined by the appended claims.

1 claim:

1. A delay action fuse for a rotatable projectile comprising a primer for detonating an explosive charge, a firing pin mounted for pivotal movement about an axis parallel with the axis of rotation of said projectile in response to centrifugal force for partially arming the fuse, said pin being slidably mounted for movement to a ntllyarrnefl posi'tion in response to impact of said projecti'l'e, and spring means for rotating the firing pin into engagement with the primer when the centrifugal force is reduced sufficiently to be overcome by the torsion exerted by the spring.

2. A fuseas in claim 1, and guide means for limiting .the movement of the firing pin in response to the impact and for retaining the firing pin correctly positioned to engage the primer in response to rotation of said firing pin.

3. A fuse as in claim 1, and a spring pressed detent for engaging and holding the firing pin in a fully armed position, and means for camming the detent to an inoperative position when the centrifugal force acting on the firing pin is substantially reduced so that the pressure of the spring will overcome the centrifugal force and the resistance of the detent, for rotating the firing pin against the primer to detonate the same.

4. A delay action fuse for rotatable projectiles comprising a fuse housing, a pair of primers disposed in the housing at an obtuse angle to one another, a pair of shafts mounted in the housing, a firing pin carrier eccentrically mounted on each shaft and slidably and turnably connected thereto, a spiral spring mounted on each shaft, each spring having an end connected to the carrier and an opposite, anchored end, said springs functioning initially to resist the outward swinging movement of the carriers, produced by the centrifugal force resulting from the rotation of the projectile in flight in which the fuse is mounted, and thereafter functioning to resist the forwardmovement of the carrier, in response to inertia upon impact of the projectile with a target, and said carriers having projections forming firing pins, said springs acting to swing the carriers inwardly on the shafts toward the primers when the centrifugal force is substantially reduced by contact of the projectile with the target, and said projections being disposed at an angle to the planes of the carriers so that they will engage and detonate the primers when the carriers are swung inwardly.

'5. A fuse as in claim 4, and a sleeve turnably mounted on each of the shafts and to which said springs are an 'chored, said sleeves being turnable on the shafts for varying the tension of the springs.

6. A fuse as in claim 4, andspring detents associated 'with the carriers and shafts and functioning after move- -ment-of the carriers forward by inertia, to yieldably resist the initial inward movement of the carriers so that the centrifugal pull on the carriers will substantially cease before the carriers are swung inwardly, and so that the firing pins will be forcefully moved into engagement with the primers when the resistance of the detents on the carriers is released.

7. A fuse as in claim 4, and means for retaining the carriers in their outermost positions until the centrifugal force has been reduced to substantially less than the force of the springs, so that the carriers will be swung forceably inward when released by said means.

8. A delay action fuse for rotatable projectiles comprising an eccentrically mounted carrier containing a firing pm, said carrier rotatably mounted to swing outward by centrifugal force when the projectile, containing the fuse is in flight, said carrier being slidably mounted for forward movement by inertia upon impact of the projec tile with a target, spring means for swinging the carrier inward upon substantial cessation of the centrifugal force, and a primer disposed to be engaged by the firing pin when the carrier is swung inward.

9. In a delay action fuse for a rotatable projectile, a firing pin, means mounting said firing pin for translation along a first axis parallel to the axis of rotation of said projectile from a first rearward position to a second forward, armed position, said means also mounting said firing pin for rotation into firing position about said first axis, spring means urging said firing pin into said first position in translation and toward firing position in rotation,

7 and a primer positioned to'be detonatedby said firing pin when said pin is translated into secondposition in 10. In a delay action fuse for a rotating projectile, a

carrier, means mounting said carrier for translation along a first axis parallel with the axis of rotation of said projectile, from a first rearward position to a second forward, armed position, said means .also'mounting .saidcarrier for rotation about said first axis away from a detonating position in response to centrifugal force, a firing pin on said carrier, a spring urging said carrier into said first position in translation and into firing position'in rotation, and a primer positioned to be engaged by said firing pin only when said carrier .is translated into sec ond position in response to impact of said projectile and then rotated into firing position by said spring on decrease of rotation of said projectile to a predetermined rate.

11. In a, delay action fuse for a rotating projectile, a housing, a shaft fixed in said housing, a carrier journaled axis of said shaft and rotatable thereon from a radially on said shaft for rotationthereon and axial translation therealong, said carrier having its center of gravity offset from the axis of said shaft, said carrier being axially translatable on said shaft from a first,: rearward, unarmed inward'firing'position to a radially outward safe position in response to spinning of the projectile about its longitudinal axis, a coil spring about said shaft and having one end 'connectedwith said carrier to'simultaneously urge the same toward said rearward and inward firing positions, I I a firing pin fixed tosaid carrier, and a primer fixedly carried by said housing in position to be initiated by. said firing pin only when said carrier has slid to said for ward position in response to impact and has been rotated by said spring to said inward position, in the. orderrecited.

14. In a delay actionfuze for a projectile'having a longitudinal axis of spin, a housing adapted for securement to the projectile anddefininga closed chamber, there being a threaded bore in said housing parallel with said axisand opening rearwardly into said chamber, a sleeve having its forward. end threaded into said boreand its.

rearward end extending into said chamber, a shaft fitting said sleeve and fixed with said housing, said shaft having an enlarged headed end within said chamber in rear.-

Wardly spaced relation with the contiguous end of said sleeve, a firing pin carrier translatably and rotatably" I mounted uponsaid enlarged end-of saidshaft, said carrier position to a second, forward, armed position, and rotat ably away from a detonating position by centrifugal force about said first axis, a firing pin fixed to said carrier, a coil spring about said shaft and urging said carrier into first position in translation and into detonating position in rotation, and a primer carried bysaid housing and positinned to be engaged and detonated by said firing'pin only When-said carrier is translated into second position against the action of said spring in response to impact of saidprojectile, and subsequently rotated into detonating position by said spring following cessation of rotation of said pro jectile.

12. A fuse as in claim 9, and means for adjusting the torsion of said spring means to vary the maximum rate of spin at which said firing pin is. rotated into firing position 13. In a delay action fuse for a projectile having a longitudinal axis of rotation, a housing, a shaft fixed in said housing parallel with said axis, a carrier slidable on and along said shaft from a rearward position to a forward position relatively to said housing in response to impact, said carrier having its center of gravity offset from the having its centroid radially offset from the axis ofsaid shaft and a single coil spring about said shaft and sleeve, said'spring being secured at one end to said sleeve and. at

its other end to said carrier to yieldingly urge the latter axially into safe position and rotationally into firing position.

I 15. A fuze as recited in claim 14, said'carrier being translatable forwardly to armed position in response'to impact, tospan the space between the contiguous end of said sleeve and enlarged end of said shaft, a'nd'detent meanson said carrier to engage Within said space and hold said carrier. in armed position and rotatable in response to urge of said spring.

References Cited in thefile of this patent UNITED STATES PATENTS 1,311,081 Martin July 22, 1919 1,534,012 Watson Apr. 14, 1925 FOREIGN PATENTS 177,271 Germany Oct. 18, 1906 162,099 Great Britain Apr. 28, 1921 43,453 France Mar. 19, 1934 

